1. Field of Invention
The invention relates to a method for the processing of print products, wherein the print products are supplied individually along a feeding section and are transferred individually to a further processing section to be processed further. The invention also relates to an apparatus for realizing methods of this type.
2. Related Art
When processing print products, these products are imprinted with the aid of a rotary press, operating at a printing speed that is normally predetermined, and are then subjected to further processing operations, such as, for example, folding, cutting and trimming, stitching, inserting or the like. The processing speeds of the individual further processing operations can vary. With a continuous production, also called an “online production,” the total production speed must be adjusted to the further processing speed of the further processing operation with the slowest speed, resulting in a reduction of the productivity on the whole.
To avoid these problems, it has already been proposed that, following the individual further processing steps, the print products be stored temporarily in buffer systems such as, for example, by winding them around a winding system. Then, at an appropriate time, those print products temporarily stored in the buffer system may be unwound from the winding system and subjected to the further processing steps. As a rule this is tied to considerable expenditure since it requires on the one hand that a buffer system be made available and, on the other hand, that additional means be provided for the standard buffer systems, e.g. winding systems or the like, for the further processing of the print products in the intermediate storage. Corresponding methods are described, for example, in the documents EP 0 272 398 A1, WO 94/02398 and CH 664 138 A5 as well as in the CH 655 076 A5, each of which is incorporated herein by reference.
In view of the problems described in connection with the use of buffer systems, it has been proposed that the flow of print products, reaching a slow-operating further processing device, if applicable be divided and conveyed to several further processing devices. In that case, only each second, third or fourth print product, for example, of the incoming product flow is supplied to a specific further processing device, so that even with a particularly high feeding speed, a slow further processing with two, three or more processing systems is possible without having to reduce the production speed on the whole. In the process, the flow of supplied print products is divided according to fixed division ratios into two, three or more partial flows. It has turned out that a high production speed can be achieved with this method, to be sure, but that the capacity of the further processing devices frequently is not utilized completely.
When using known methods for dividing the flow of supplied print products, the insufficient use of the capacity of further processing devices results from the fact that the flows are divided according to fixed ratios which are determined by the number of available further processing devices. The speed of the further processing device is consequently tied directly to the feeding speed and cannot be influenced further.
In view of the above described problems, it is an object of the present invention to provide methods for the processing of print products which allow an optimum utilization of the capacity of individual further processing devices, without reducing the production speed on the whole, as well as to provide apparatuses for realizing the aforementioned methods.